<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>控制html的CSS外部结合</title>
    <!--<link rel="stylesheet" href="css/a.css">-->
    <style>
        @import "css/a.css";
    </style>
</head>
<body>
    <div>Hello CSS，键值冒,内部选择器定位</div>
</body>
</html>